WO2016156001A1

WO2016156001A1 - Valve, in particular vacuum valve

Info

Publication number: WO2016156001A1
Application number: PCT/EP2016/055136
Authority: WO
Inventors: Klaus Albrecht
Original assignee: Vat Holding Ag
Priority date: 2015-03-27
Filing date: 2016-03-10
Publication date: 2016-10-06
Also published as: MY184862A; JP6843058B2; KR102504116B1; CN107407427B; JP2018515720A; US20180051813A1; KR20170129714A; US10364899B2; CN107407427A

Abstract

The invention relates to a valve (1), in particular a vacuum valve, comprising at least one valve housing (2), at least one closure element (3), and at least one valve seat (4). The valve seat (4) surrounds at least one valve opening (5) of the valve (1), and the closure element (3) can be moved back and forth between at least one open position, in which the closure element (3) at least partly releases the valve opening (5), and a closed position, in which a sealing surface (8) of the closure element (3) is pressed against the valve seat (4) in order to close the valve opening (5), by means of at least one closure element drive (6, 7). At least one surface (9) of the valve (1) has an average surface roughness RZ less than or equal to 0.4 um, preferably less than or equal to 0.25 um.

Description

Valve, in particular Vakuu mventi l

The present invention relates to a valve, in particular a vacuum valve, with at least one valve housing and at least one closure member and at least one valve seat, wherein the valve seat surrounds at least one valve opening of the valve and the closure member of at least one

Closure member drive between at least one open position in which the closure member at least partially releases the valve opening, and a

Closed position in which the closure member with a sealing surface of

Closure member is pressed to close the valve opening to the valve seat, is movable back and forth.

Valves of this type are used, in particular, as vacuum valves and the like. then used when manufacturing or machining processes in a defined atmosphere under defined pressure conditions and in particular in the so-called vacuum, ie in the vacuum must be performed. The valves can be used to provide chambers such as e.g. Process chambers or transfer chambers lockable and pressure-resistant to connect with each other. The valve housing of the valve is often in such applications on a chamber wall of the

appropriate chamber attached. Also integrated embodiments are possible. The valve opening of the valve then usually aligned with a corresponding chamber opening. If the closure member is in the open position, the valve opening is at least partially released and workpieces to be processed can be introduced into or removed from the corresponding chamber. If the valve is in the closed position, then the chamber is sealed and the conditions required for the respective process, in particular pressure conditions, can be set. In valves of the above type but it can also be so-called metering valves, in which the valve serves to meter a fluid, in particular gas, into a chamber or the like.

In order to be able to carry out the respective processes, it is usually very important to reduce the entry, the generation and the transport of undesired particles as far as possible or, ideally, to completely suppress them.

The object of the invention is to improve valves of the type mentioned above in this regard.

For this purpose, it is proposed according to the invention that at least one surface of the valve an average roughness RZ less than or equal to 0.4 μηι (microns), preferably less than or equal to 0.25 μιτι having. In other words, it is provided according to the invention, at least certain surfaces of the valve very smooth, so with a very low roughness

embody. In this way, as will be explained in detail below, both the adhesion and the generation of interfering particles can be significantly reduced. The roughness indicating average roughness RZ is determined according to DIN EN ISO 4287. This need not be further explained. The measurement of the RZ value is preferably by means of non-contact

To perform interference microscopy. Suitable meters available on the market for this purpose are e.g. the white light interferometer WLI MarSurf CW100 from Mahr, the Wyko NT1 100 from Veeco and the InfiniteFocus G5 from Alicona.

The surfaces of the valve with the roughness or smoothness according to the invention are preferably gloss-milled and / or bright-turned surfaces. In this sense, a method for producing a valve according to the invention provides that the surface is milled and / or lathed. Through the Glanzfräsen and the gloss turning a micro ridge formation on the

Profile tips in the surface can be avoided. The surface can z. B. made of aluminum or an aluminum alloy or at least have such a material. Particularly preferred in this case are aluminum alloys of series 5000 or series 6000 according to EN 573-3: 2007 (D). Particularly preferred aluminum alloys are the types 5083, 6061 and / or 6082 mentioned in this standard. Alternatives to aluminum exist, for example, in stainless steel. It can therefore also be provided that said surfaces of the valve are made of stainless steel or have such a material. Particular preference is given to surfaces according to the invention in what are known as dynamic seals, that is to say in the case of seals which are opened and closed during the operation of the valve. Thus, particularly preferred embodiments of the invention provide that the surface with the present invention low roughness or high G lattheit on the valve seat of

Valve housing and / or is formed on the sealing surface of the closure member. As a result, the particle formation at friction surfaces during opening and closing of the closure member compared to the prior art is significantly reduced, especially in applications where a seal such. a rubber or other elastomeric seal of the valve is pressed in the closed position to the surface and the seal in the open position is lifted from the surface again. As a result of the smooth surface according to the invention, the abrasion on the seal during opening and closing of the closure member is reduced to such an extent that, compared to the prior art, the result is a very greatly reduced or no particle formation at all. Elastomer seals can without

Additional treatment can be used.

Smooth surfaces according to the invention can be used not only in dynamic seals but also in static seals to reduce particle generation. In this sense, it can therefore also be provided that the surface is formed on a sealing seat of the valve, to the one

Seal is permanently pressed during operation of the valve. It should be noted that it is due to pressure build-up and pressure reduction in the area Such static seals can lead to a certain movement of the components in contact with each other, so that it makes sense here to reduce as much as possible by a correspondingly smooth surface particle generation or completely avoided.

In addition to the above sealing surfaces, valve seats and sealing seats can

surfaces according to the invention but also be used on other portions of the valve. A particularly preferred example of this is to mention that the surface is formed at least on a portion of the valve housing and / or the closure member, which comes during operation of the valve with process fluids, in particular with process gases, into contact. In this way, it is prevented, in particular, that particles can settle on the surfaces of the abovementioned portions of the valve housing or of the closure member that are very smooth in accordance with the invention. As a result, these surfaces are also very easy and effective to clean. Another effect here is that due to the low degree of particle adhesion to these surfaces a faster

Pumping the process fluids or gases from the equipped with valves according to the invention process chambers is possible. Particularly preferred are the surfaces of the valve with the mentioned

According to the invention, low roughness is formed as optically reflecting surfaces. This also prevents these surfaces and thus also the valve housing and / or the closure member by heat radiation in the

Heat process chambers unnecessarily. The heat radiation is at the

surfaces according to the invention at least largely reflected and thus remains energy saving by re-radiation process. It thus comes to a lower heating of the components of the valve. This can also be done

less expensive materials such as Elastomeric gaskets for hotter processes or aluminum or aluminum alloys instead of austenitic steel or

Stainless steel can be used. In addition, it has to take into account lower temperatures in the valve drive and generally lower thermal component loads. In this sense, preferred embodiments of the Invention, that the surface has a reflectance for electromagnetic radiation of at least 0.8, preferably of at least 0.9. These reflectivities should preferably in the wavelength range between 0.01 μιτι (microns) and 1000 μιτι, in particular in the field of heat so

Infrared radiation and visible light can be achieved. The reflectance includes both the directionally reflected and the scattered portion of the incident electromagnetic radiation and may be e.g. be measured with an integrating sphere. Inventive valves can be designed such that the valve opening serves to allow workpieces to be processed to be transported through the valve opening. The size of the valve opening can then be adapted to the size of the workpieces to be transported. In these

Embodiments, the closure member or the closure members may be plate or plate-like design. Such valves can also as

Transfer valves are called. It can be just as good

Valves according to the invention but also act as so-called gas metering valves. In these, the occlusive organs may e.g. be formed in the shape of a tip, conical or the like. In the case of dynamic sealing surfaces, the known seal can be arranged both on the valve seat of the valve housing and the sealing surface of the closure member. The respectively

Corresponding or with the seal in the closed position of the

Locking member cooperating other surface then conveniently has the inventive smoothness or low roughness.

As already indicated, valves according to the invention are preferably used in so-called vacuum technology. Usually one speaks of

Vacuum technology, when operating conditions with pressures less than or equal to 0.001 mbar (millibars) or 0, 1 Pascal are achieved. Vacuum valves are valves that are designed for these pressure ranges and / or corresponding differential pressures to the environment. But one can generally speak of vacuum valves when they are designed for pressures below normal pressure, that is below 1 bar. Further advantages and details of the invention will be explained by way of example below with reference to exemplary embodiments. 1 to 5 representations of a first embodiment of a valve according to the invention;

6 and 7, a second embodiment of a valve according to the invention and Fig. 8 shows a third embodiment of a valve according to the invention. In the first embodiment, which is shown schematically in Figures 1 to 5, it is a vacuum valve in which two closure members 3 are present, which each have an L-shaped movement between their

Open position according to FIG. 5 and their closed position according to FIG. 3 perform. Such valves 1 are generally referred to in the prior art as L-valves.

1 shows an external view of the valve housing 2 of the valve 1. In Fig. 1, the closure members 3 are in their open position in which they fully release the valve opening 5 in this embodiment. In FIGS. 2 to 5, longitudinal sections through the valve 1 are shown in each case. In Fig. 2 it is shown how the valve 1 is arranged between two only partially drawn chambers 12 to connect the chamber openings 1 3 closed by means of the valve opening 5. In the chambers 1 2, it may, as in the prior art known per se, to process chambers in which processing and / or

Manufacturing processes under defined atmosphere and defined

Pressure ratios are performed, act. But it can just as well be so-called transfer chambers, which serve to

to transfer machining workpieces from one process chamber to another process chamber. In Figs. 3 to 5, the chamber 12 are not shown.

To the closure members 3 of this embodiment between the

Opening position shown in FIG. 5 an intermediate position shown in Fig. 2 and 4 and to be able to move the closed position shown in FIG. 3 back and forth, are in this embodiment, two shutter organ drives 6 and 7th

intended. By means of the closure member drive 6, the closure members 3 are moved in the directions of movement 16 between the open position shown in FIG. 5 and the intermediate position shown in FIGS. 2 and 4 in linear movements back and forth. In the illustrated embodiment, it is the

Closing member drive 6 to a piston-cylinder assembly with the cylinder 14 and the movable therein in a known manner piston 15. The piston 15 is fixedly connected to the valve rod 19. On the side facing away from the piston 1 5 side of the valve rod 19 are the shutter organ drives 7 and the

Locking organs 3. In this embodiment, the

Closing organ drives 7 as a piston-cylinder arrangement, each with a

Cylinder 14 and a piston 1 5 formed. 15 each on each piston

Closing member drive 7, a closure member 3 is attached. By means of

Locking organ drives 7, the closure members 3 between the

2 and 4 and the closed position shown in FIG. 3 in the second, here also linear, directions of movement 17 are moved back and forth. The formation of such closure organ drives 6 and 7 is known per se in the prior art and is shown here only schematically and by way of example. Basically, the invention with a variety of known per se

Closing organ drives 6 and / or 7 are realized. It can only be one

Closure member drive or even a plurality of closure organ drives for a valve according to the invention may be provided. The closure members 3, which are here plate-shaped or dish-shaped, are in all their operating positions in an interior 21 of the

Valve housing 2. The valve seats 4, against which the closure members 3 are pressed in their closed position, are in the embodiment shown on the corresponding inner sides of the valve housing 2. To the

Closure members 3 each sealing surfaces 8 are formed, which in this

Embodiment in each case carry the seals 10, which pressed in the closed position of the closure members 3 to the valve seats 4 and in the intermediate position and are lifted in the open position of the valve seats 4. Of course, the seals 10 could also be formed on the valve seats 4 and be pressed only in the closed position to the sealing surfaces 8 of the closure members 3. The seals 10 may also be integrally integrated into the valve seats 4 or the sealing surfaces 8. With appropriate design of valve seats 4 and sealing surfaces 8 can be completely dispensed with separate seals 10.

In order to carry out maintenance work on the closure members 3, the shutter organ drives 7 or generally in the interior 21 of the valve housing 2, a part of the valve housing 2 from the remaining valve housing 2 is removably formed in the form of the lid 18. To seal the lid also seals 10 are provided, which are each pressed against the corresponding sealing seat 1 1 of the lid 18. These features of the valve 1 or vacuum valve are known per se in the prior art and have been explained here by way of example only.

Following the invention, it is provided in this exemplary embodiment that various surfaces 9 on the valve housing 2 and on the closure member 3 in the sense of reducing particle formation and particle adhesion have an average roughness RZ less than or equal to 0.4 μm, preferably less than or equal to 0.25 μm. exhibit. In the exemplary embodiment shown, these are first of all the valve seats 4, which are designed with correspondingly smooth surfaces 9 according to the invention. The seal 10 on the closure members 3 and the valve seats 4 together form each dynamic seals in which it when opening and closing the

Closure members 3 by friction in the prior art to particle formation occurs. Due to the inventive design of the valve seats 4 in the form of correspondingly smooth surfaces 9, the particle formation at these friction surfaces is significantly reduced compared to the prior art or preferably completely avoided. The sealing seats 1 1 on the cover 18 and their associated seals 10 in this embodiment form so-called static seals, which are not opened during normal operation of the valve 1 or separated from each other. Nevertheless, it comes to the pressure build-up and the pressure reduction on these sealing surfaces to a certain extent the movement and thus in the prior art also to some extent undesired particle formation. To avoid this, in the embodiment shown here, the sealing seats 1 1 on the lid 18 are also designed as surfaces 9, which have an average roughness RZ less than or equal to 0.4 μιτι, preferably less than or equal to 0.25 μητι. As a result, particle formation is also at least reduced, preferably completely avoided, at these so-called static sealing surfaces.

In addition, in this exemplary embodiment, smooth surfaces 9 are formed according to the invention on all subregions of the valve housing 2 and of the closure member 3, which come into contact with process fluids or gases during operation of the valve 1. This leads to a significantly lower adhesion of particles to these surfaces of the

Valve housing 2 and the closure members 3, which can be cleaned much better these surfaces. In addition, the low allows

Particle adhesion to these surfaces a faster Druckab- and -aufbau in the valve 1 and in the chambers 12th

Preferably, these surfaces 9 are designed as optically reflecting surfaces, which preferably have a reflectance for electromagnetic radiation of at least 0.8, preferably of at least 0.9. This leads to an increased re-radiation of the resulting in the chambers 12

Process heat. An unwanted heating of the corresponding surfaces or walls is greatly reduced or avoided by this strong reflection or reflection of the heat radiation, resulting in a total of less energy loss and thus lower energy consumption in the implementation of the processes in the chambers 12. In addition, again at the beginning already referenced further advantages of such highly heat-reflecting surfaces 9.

In this first exemplary embodiment, therefore, all relevant surfaces are designed as surfaces 9 according to the invention having a roughness according to the invention. Of course, this need not be so, it may also be less and / or other surfaces on such or other valves 1 equipped with according to the invention smooth surfaces 9. By way of example with reference to the exemplary embodiments in FIGS. 6 to 8, it will be illustrated by way of example that smooth surfaces 9 according to the invention can of course also be used in completely different valve types known per se. In the embodiment in FIGS. 6 and 7, this is an example of a so-called shuttle valve, in which the closure members 3 together with the valve stem 19 are not moved back and forth linearly between the open position and the intermediate position as in the first embodiment, but between these positions in the Movement directions 16 shown in Fig. 7 are pivoted about the axis 20. The movement of the closure members 3 between the intermediate position shown in FIG. 6 and the closed position, as in the first embodiment by means of the shutter organ drives 7 in the second directions of movement 1 7.

FIG. 7 shows, in a side view from the direction of one of the closing chambers 12, the valve 1 shown here as a pendulum vacuum valve, as shown in FIG. 6, once again with the valve housing 2 shown transparently. Also in Fig. 7 is a highly simplified, schematic drawing. The closure members 3 and the valve rod 19 are in Fig. 7 in the solid view in the intermediate position shown in FIG. 6, in which the closure members 3 already cover the valve opening 5, but not yet pressed against the valve seats 4. In addition, in Fig. 7 nor the open position of closure member 3 and valve rod 19 is shown in dashed lines. Fig. 7 can be easily seen as the closure members 3 together with valve stem 19 between the intermediate position and the open position in the first directions of movement 16 of the closure member drive 6 to the Swivel axis 20 are pivoted back and forth. This is known per se and need not be explained further, as well as the sealing of the valve rod 19, not shown in detail here, against the valve housing 2, which can be achieved, for example, by means of a corresponding bellows seal or the like.

Apart from the differences described when moving the

Closure members 3 between the open position and the intermediate position, this second embodiment according to FIGS. 6 and 7 otherwise executed in the same way as the first embodiment, so that reference may be made to the above description. This is especially true for the

inventive design of the various surfaces 9 and the advantages achieved thereby.

8 shows by way of example and schematically a third type of valves 1, and

Vacuum valves in which smooth surfaces 9 according to the invention can be used. This is a so-called wedge valve, in which the closure member 3 is wedge-shaped. This valve 1 requires only a single closure member drive 6, which adjusts the closure member 3 between the closed position shown in Fig. 8 and the open position, not shown here, in which the valve member 3, the valve opening 5 releases. The movement of the closure member 3 takes place in this embodiment only in the first directions of movement 16, that is exclusively linear in one direction and the opposite direction. Such wedge valves are known per se and need not be explained in detail. But according to the invention is also in this

Embodiment now provided that the valve seat 4, the sealing seat 1 1 and all during the operation of the valve 1 with process fluids or gases coming into contact portions of the valve housing 2 and the closure member 3 are equipped with surfaces 9 according to the invention, which an average

Roughness RZ less than or equal to 0.4 μιτη, preferably less than or equal to 0.25 μηη have. Otherwise, as far as applicable, reference may be made to the first exemplary embodiment and its description, so that supplementary explanations regarding this third exemplary embodiment do not appear necessary. Finally, it is pointed out again that apart from the valve types explicitly shown, of course, a variety of other valves and

Valve types can be equipped with surfaces 9 of the invention. As further examples, without limitation of generality, angle valves and so-called monovat valves with only one closure member or plate and finally, if applicable, all other known valve types should be mentioned. These can have one, two or even more valve drives.

Legend to the reference numbers:

1 valve

2 valve housing

3 closure member

4 valve seat

5 valve opening

6 Locking device drive

7 Lock actuator

8 sealing surface

9 surface

10 seal

11 sealing seat

12 chamber

13 chamber opening

14 cylinders

15 pistons

16 first directions of movement

17 second directions of movement

18 lids

19 valve rod

20 pivot axis

21 interior

Claims

Patent claims

Valve (1), in particular vacuum valve, with at least one valve housing

(2) and at least one closure organ

(3) and at least one valve seat (4), the valve seat

(4) surrounds at least one valve opening (5) of the valve (1) and the closure member (3) of at least one closure member drive (6, 7) between at least one opening position in which the closure member (3) at least partially releases the valve opening (5). , and a closed position in which the closure member (3) with a sealing surface (8) of the closure member (3) for closing the valve opening

(5) is pressed against the valve seat (4) and can be moved back and forth, characterized in that at least one surface (9) of the valve (1) has an average roughness depth RZ less than or equal to 0.4 μm, preferably less than or equal to 0 .25 μητι.

Valve (1) according to claim 1, characterized in that the surface (9) is a polished and/or polished surface and/or an optically reflective surface.

Valve (1) according to claim 1 or 2, characterized in that the

Surface (9) has a reflectance for electromagnetic radiation of at least 0.8, preferably at least 0.9.

Valve (1) according to one of claims 1 to 3, characterized in that the surface (9) consists of aluminum or an aluminum alloy or stainless steel or has such a material.

Valve (1) according to claim 4, characterized in that the surface (9) consists of an aluminum alloy of the 5000 series or the 6000 series or has such a material.

6. Valve (1) according to one of claims 1 to 5, characterized in that the surface (9) on the valve seat (4) and / or on the sealing surface (8) of the

Closure member (3) is formed.

7. Valve (1) according to claim 6, characterized in that in the

Closed position a seal (10) of the valve (1) is pressed against the surface (9) and the seal (10) in the open position of the

Surface (9) is lifted.

8. Valve (1) according to one of claims 1 to 7, characterized in that the surface (9) is formed on a sealing seat (1 1) of the valve (1), on which a seal (10) is formed during operation of the valve (1) is permanently pressed.

9. Valve (1) according to one of claims 1 to 8, characterized in that the surface (9) is formed at least on a partial area of the valve housing (2) and / or the closure member (3), which during operation of the valve ( 1 ) comes into contact with process fluids.

10. A method for producing a valve (1) according to one of claims 1 to 9, characterized in that the surface (9) is milled to a shine and / or turned to a shine.